manufacturers had had a better view of their suppliers below the tier i then they could have taken steps to to diversify supply and mitigate the risk.
high tech companies such as cisco have now become much more proficient at identifying components which may be at risk from disruption,and implementing a multi-source strategy.
Another reason why supply chain risk has become a pressing issue is the environment of increasingly inter-related networks in which we work. There is still very little understanding of how they interact. This is a real worry,not just for transport networks,as IT,communications,financial,energy and even society is affected. One example of this relates to the bombing a few years ago on the london underground and buses